Permanent form for precast tilt-up concrete modules and process

ABSTRACT

A SPECIAL PERMANENT FORM MEMBER SERVES AS THE FORM FOR A PRECAST TILT-UP CONCRETE PRODULE AS IT IS POURED ON A CURING FLOOR. THE FORM MEMBER REMAINS IN PLACE DURING TILT-UP AND SERVES AS A JOINT AGAINST THE PILASTER. THE FORM MEMBER SERVES AS THE CONCRETE MODULE FORM AND AS THE FINISHED CONCRETE MODULE EDGE AND IS FORMED WITH A PLURALITY OF WEBS WHICH EXTEND ALONG THE EDGE OF THE CONCRETE MODULE. THE EDGES OF THE FORM MEMBER ARE FOLDED IN TO BE LOCKED INTO THE CONCRETE OF THE PRECAST MODULE. THE FORM MEMBER IS USED AS A FORM FOR THE SIDES, TOP AND BOTTOM OF THE CONCRETE MODULE. KNOCKOUTS ARE PROVIDED FOR TRANSVERSE REINFORCING BARS SO THAT THE FORM MEMBERS CAN BE CLAMPED IN PLACE TO RESIST POURING DEFORMATION AND THE REBARS EXTEND INTO THE PILASTERS WHEN   THE FINISHED CONCRETE MODULES ARE ARE ERECTED. REINFORCEMENT OF THE TOP AND BOTTOM FORM MEMBERS IS MANAGED BY EXTERIOR STRONGBACKS. CORNERS ARE EMPLOYED ON THE CURING FLOOR TO AID IN INITIAL SETUP. SPECIAL REBAR CLAMPS ARE PREFERABLY EMPLOYED TO TRANSFER POURING LOAD TO THE REBARS. BY EMPLOYMENT OF THE PERMANENT FORM MEMBER, FORMS CAN BE MORE QUICKLY PRODUCED, PRECAST TILT-UP CONCRETE MODULES CAN BE MORE CLOSELY SPACED UPON THE POURING FLOOR, AND CLEANUP MINIMIZED FOR A QUICKER SETUP INTO BUILDING CONFIGURATION.

Oct. 5, 1971 THQMAS 3,609,935

PERMANENT FORM FOR PRECAST TILT-UP CONCRETE MODULES AND PROCESS FiledMay 1, 1969 5 Sheets-Sheet 1 PIZIOQ ART DELMAE L. 7 /401405 INVENTOR.

T12 44 112T 11-+ 41mm! 06L 5, 1971 THOMAS PERMANENT FORM FOR PRECASTTILT-UP CONCRETE MODULES AND PROCESS Filed May 1, 1969 5 Sheets-Sheet 3El Q05 Dam/2,2 L. 'Iyomns INVENTOR.

A T TOQAff v 06L 5, 1971 THOMAS 3,609,935

PERMANENT FORM FOR PRECAST TILT-UP CONCRETE MODULES AND PROCESS FiledMay 1. 1969 5 Sheets-Sheet 5 m ZZ se sz 15 .84 82 84 80 $1 q.l

D151. 442 L- THoMflS INVIfN'I'OR.

4 TTOQAJ'EY Oct. 5, 1971 D. THOMAS PERMANENT FORM FOR PRECAST TILT-UPCONCRETE MODULES AND PROCESS Filed May 1, 1969 5 Sheets-Sheet 4 DEL/wareL- THoMfl INVENTOR.

D. L. THOMAS Oct. 5, 1971 PERMANENT FORM FOR PRECAST TILT-UP CONCRETEMODULES AND PROCESS 5 Sheets-Sheet 5 Filed May 1, 1969 DEL/W42 L. THoMAsINVENTOR.

w 717 flrfaQa/EY United States Patent 3,609,935 PERMANENT FORM FORPRECAST TILT-UP CONCRETE MODULES AND PROCESS Delmar L. Thomas, LosAngeles, Calif. (13449 Branford St, Arleta, Calif. 91331)Continuation-impart of application Ser. No. 803,534, Mar. 3, 1969. Thisapplication May 1, 1969, Ser. No. 826,771

Int. Cl. E04b 1/35; E04g 21/12 US. Cl. 52-745 7 Claims ABSTRACT OF THEDISCLOSURE A special permanent form member serves as the form for aprecast tilt-up concrete module as it is poured on a curing floor. Theform member remains in place during tilt-up and serves as a jointagainst the pilaster. The form member serves as the concrete module formand as the finished concrete module edge and is formed with a pluralityof webs which extend along the edge of the concrete module. The edges ofthe form member are folded in to be locked into the concrete of theprecast module. The form member is used as a form for the sides, top andbottom of the concrete module. Knockouts are provided for transversereinforcing bars so that the form members can be clamped in place toresist pouring deformation and the rebars extend into the pilasters whenthe finished concrete modules are are erected. Reinforcement of the topand bottom form members is managed by exterior Strongbacks. Corners areemployed on the curing floor to aid in initial setup. Special rebarclamps are preferably employed to transfer pouring load to the rebars.By employment of the permanent form member, forms can be more quicklyproduced, precast tilt-up con crete modules can be more closely spacedupon the pouring floor, and cleanup minimized for a quicker setup intobuilding configuration.

CROSS REFERENCE.

This application is a continuation-in-part of copending patentapplication entitled Permanent Form for Precast Tilt-Up Concrete Modulesand Process and Article, Ser. No. 803,534, filed Mar. 3, 1969 and nowabandoned.

BACKGROUND OF THE INVENTION (1) Field of the invention This invention isdirected to a permanent form for precast tilt-up concrete modules, theprocess for producing the modules, the articles employed in creating themodules and the buildings produced by employment of these modules.

(2) Description of the prior art The pouring and tilt-up of modules ofsidewalls for building construction and other uses is well known. Tiltupmodules are presently Widely used in building modern factories andwarehouses. Furthermore, they may be employed in producing walls forflood control channels and in other locations where large concretemodules are required. Modern engineering has produced techniques forhandling very large modules. Panels more than 24 feet in one dimensionare often employed in such construction. Furthermore, such modulescommonly range in thickness from 6 inches to inches. All dimensionsdepend upon the size requirement of the building, together with thestructural strength required. Thicker modules are employed where largeloads are anticipated.

However, present-day techniques of producing precast tilt-up concretemodules employ wooden forms which are laid out upon the curing floor forpouring and which Patented Oct. 5, 1971 are removed after pouring.Repetitive use of the form may be obtained but only for a few uses, atbest, before the form is worn out or otherwise becomes unsuitable forre-use, thus entailing expensive replacement. Furthermore, considerablelabor is expended in the placement and removal of the module forms, forsuch forms must be strong during pouring to minimize deflection.Additionally, the employment of wooden forms necessitates a fairlysimple edge profile which does not fit the optimum needs in joining witha pilaster.

The employment of permanent form structure which can be easily laid outon the curing floor and permanently secured to the edges of a concretetilt-up module overcomes the foregoing and other disadvantages andprovides a superior product. While permanent forms have been known inthe field of pouring concrete in horizontal slab work, those arecompletely unsuitable for employment in tilt-up concrete moduleconstruction.

SUMMARY OF THE INVENTION In order to aid in the understanding of thisinvention, it can be stated in essentially summary form that it isdirected to a permanent form member for precast tilt-up concretemodules, together with the process and articles employed in producing atilt-up concrete module incorporating the form member as well as theproduction of a building by employment of the articles in the productionof a concrete module and the employment of the module in buildingconstruction. The form member has a plurality of angular webs whichdefine a plurality of channels along the outer, finished edge of themodule. Inturned edges on the form member lock into the concrete toprotect the module edges and define a proper surface for pilasterjoining. The form members in the form are arranged so that transversereinforcing bars can extend therethrough, and reinforcing bar clampsprovide rigidity to the side form members during pouring. Additionally,and separately, a particular form of the reinforcing bar clamp aids inspeedy assembly. Furthermore, corners are employed on the curing floorfor laying out the forms prior to pouring. Strongbacks are secured tothe portions of the form which become the top and bottom of the finishedtilt-up module.

Accordingly, it is an object of this invention to provide a permanentform for precast tilt-up concrete modules, which form can be laid outupon the curing floor for the pouring of concrete therein, and the formremains upon the module and is tilted up into position. It is a furtherobject of this invention to provide a permanent concrete form forprecast tilt-up modules wherein the form is of such construction andconfiguration as to provide a superior joint with pilasters pouredbetween adjoining modules. It is another object to produce a building byproducing a plurality of precast tilt-up concrete modules by employmentof the permanent form member of this invention, including production ofthe modules on the pouring floor and tilt-up of the modules intobuilding Wall position.

It is still another object of this invention to provide a permanent formfor precast tilt-up concrete modules wherein the form is of maximumrigidity for the particular amount of form material so that deflectionduring pouring is minimized. It is. another object of this invention toprovide forms for precast tilt-up concrete modules wherein reinforcingbars can extend through the forms which are positioned on the sides ofthe module so that the extending reinforcing bars can be cast intojoining pilasters. It is still another object to provide a reinforcingbar clamp in association with the permanent form of this invention sothat the clamps can be quickly and tightly engaged to the reinforcingbars to inhibit deflection of the side form members of the module. It isanother object to provide a strongback which can be detachably securedto the form members which will be the tops and bottoms of the finishedtilt-up concrete module to provide adequate strength to the top andbottom form members during the pouring operation. It is a further objectto provide strongback support which supports the strongback and top formmember angularly with respect to the floor to permit casting of moduleswith angular tops.

It is another object to provide for form corners which are employed onthe curing -floor to aid in the laying out of the permanent form inpreparation for concrete pouring. It is another object to provide analternative permanent form member of such configuration as to directlyinterfit with the preferred form member so that flush wall constructionwithout the employment of pilasters can be obtained.

Still other objects, features and attendant advantages of the presentinvention, together with various modifications, will become apparent tothose skilled in the art from a reading of the following detaileddescription of the preferred embodiments constructed in accordancetherewith, taken in conjunction with the accompanying drawings whereinlike numerals designate like parts in the several figures.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a perspective view of twotilt-up concrete modules in the tilted-up position and employing thepermanent form of this invention therewith.

FIG. 2 is a fragmentary horizontal section showing adjoining prior arttilt-up concrete modules and the pilaster poured therebetween.

FIG. 3 is an enlarged fragmentary horizontal section taken generallyalong the line 33 of FIG. 1, in the same aspect as FIG. 2.

FIG. 4 is a top plan view of the permanent form of this invention laidout on the curing floor and ready for pouring.

FIG. 5 is an enlarged fragmentary perspective View taken from a cornerof the form shown in 'FIG. 4.

FIG. 6 is a perspective view of the corner employed on the curing floorto aid in setting up of the form for pouring.

FIG. 7 is an outside perspective view of the form member of thisinvention.

FIG. 8 is an inside perspective view of the form member of thisinvention.

FIG. 9 is a perspective view, with parts broken away, of an alternativeembodiment of the strongback employed with the top and bottom formmembers of the form.

FIG. 10 is a perspective view of an alternative embodiment of thereinforcing bar clamp employed to prevent deflection of the side formmembers of the permanent form of this invention.

FIG. 11 is an enlarged partial side elevational view, taken generallyalong line 11.11 of FIG. 4.

7 FIG. 12 is an enlarged partial end elevational view, taken generallyalong line 12-42 of FIG. 4.

FIG. 13 is an enlarged section taken generally along line 13--13 of FIG.11.

FIG. 14 is an enlarged side elevational view showing the alternativeclamp engaged on a reinforcing bar.

FIG. 15 is an enlarged section taken generally along line 1515 of FIG.12.

FIG. 16 is a section taken through a portion of a concrete tilt-upmodule showing the permanent form thereon.

FIG. 17 is a sectional view showing the preferred embodiment of thisinvention in engagement with another embodiment of a permanent formmember which directly interengages therewith.

FIG. 18 is an enlarged fragmentary perspective view of a form forprecast tilt-up concrete modules, which form employs wooden form memberstogether with some of the other form structures in accordance with thisinvention.

FIG. 19 is a perspective view of the preferred embodiment of thereinforcing bar clamp of this invention.

FIG. 20 is a perspective view of the preferred embodiment of thestrongback of this invention.

FIG. 21 is a perspective view of the top and bottom support brackets.

FIG. 22 is an enlarged view showing the support brackets supporting astrongback at an angle with respect to the pouring floor, whichstrongback in turn supports a top or bottom permanent form member.

FIG. 23 is an enlarged section taken generally along the line 23-23 ofFIG. 21.

DESCRIPTION OF THE PREFERRED EMBODIMENTS First referring to the priorart of FIG. 2-, portions of prior art panels 10 and 12 are showntherein. These panels were formed on a horizontal curing floor with theemployment of wooden forms. Since wooden forms were employed, the edgeconfiguration of panels 10 and 12 is necessarily fairly simple, theconfiguration including step 14 and beveled edge 16. After positioningpanels 10 and 12 in the vertical position, pilaster 18 was pouredtherebetween. Pilaster 18 was similarly formed with a beveled edge.Normally, side 20 is the inside of the building formed of panels 10 and12 because it is preferable to have the flush surface on the inside.Furthermore, the pilaster 18 extending on the exterior providesarchitectural interest. However, in other situations, side 20 may be theoutside. The beveled edges are provided because there is alwaysseparation between the panels and pilaster. This separation is primarilycaused by ambient temperature changes. Thus, this beveled edge preventsthe appearance of an unsightly crack. Since both of the facing surfacesof the panels and the pilaster are concrete, and concrete ishygroscopic, rain which engages the building at the crack seeps throughto the interior. It creeps along the concrete surfaces until theinterior at the crack is wet.

Referring to FIGS. 1 and 3, two exemplary tilt-up concrete modulesemploying the permanent form of this invention are indicated at 22 and24. In normal building construction, they are tilted up somewhat spacedfrom each other and pilaster 26 is poured therebetween. Reinforcing bars28 and 30 extend out of the edges of the modules and are engaged inpilaster 26 as the pilaster is poured therein. Again, bevels 32 and 34form a V- notch at the junction of the modules and the pilasters toeliminate any unsightly crack appearance.

Referring to FIG. 4, the permanent form is shown laid out on a curingslab 36 ready for pouring. In view of the fact that the module to bepoured therein is normally to be erected by tilting it up from itspoured position, convenient reference will be made to form member 38 asthe left form member, and form member 40 will be referred to as theright form member. Similarly, form member 42 will be referred to as thetop form member, and form member 44 will be referred to as the bottomform member. These positions refer to the finished module in the erectedposition, and it will become clear that the top and bottom form membersare identical, and the left and right form members are identical. Thus,the module can be erected with either form member 42 or form member 44at the top, and in some special circumstances it may be desirable tohave them serve as ends. However, it will become clear from thefollowing specification that the tops and bottoms are slightly differentthan the sides so that, in normal construction, the sides are normallyvertically oriented. There is no ditference in the form members, butonly in the manner of corner treatment. Thus, all form members 38, 40,42 and 44 are identical except as to length.

Referring principally to FIGS. 7, 8 and 16, the form member 40 is showntherein. As previously stated, the form members are all identical sothat description of form member 40 will serve as description of each ofthe form members. Form member 40 comprises material of substantiallyuniform thickness formed so as to have a plurality of webs angularlyrelated to each other and extending longitudinally of the form member.The webs are best illustrated at 46 in FIG. 16. Adjacent webs arepreferably positioned at 90 with respect to each other, for suchconstruction provides maximum resistance against bending in the lateraldirection out of the general plane of form member 40 for a particularweight per unit length. Furthermore, there are sufficient webs 46,joined by adjacent 90 angles to provide four points and threeintermediate channels facing in the outward direction, as seen in FIG.16, for a form member having a suflicient width to serve as a form for aprecast tiltup concrete module six inches thick. Depending upon themethod of manufacture of the form member, various numbers of points andintermediate channels may be employed. However, for the form member ofsix inch width of this exemplary illustration, four points and threechannels is considered the minimum number.

For wider form members, four points and three channels is alsoconsidered the minimum satisfactory number, although the maximum numberof channels is such that they are not dimensionally smaller than thoseindicated in the six inch thick concrete module form illustrated forFIG. 16. In this example, the preferable present material is ZA-gaugegalvanized iron, although any convenient type of material, such as othertypes of sheet metal, synthetic polymer composition material in extrudedor rolled form, with or without reinforcing or filler material, orextruded metal such as aluminum, can be employed.

The edges of the form member are finished by inturning flanges 48 and50. These inturned flanges anchor the form member into the edge of thetilt-up concrete module. Holes 52 in these flanges permit the concreteto bond through the holes in the flanges to securely lock the flangesand the entire form member in place upon the edge of the precast tilt-upconcrete module.

Additionally, the form members are provided with knockouts 54 which canbe knocked out to permit reinforcing bars to be positioned so that theyextend through the form members. In the six inch thick form illustrated,a single row of knockouts is satisfactory. However, when wider formmembers are employed for the pouring of thicker walls, more than onelayer of reinforcing bars may be desired. In this case, as many rows ofknockouts will be provided as may be required for reinforcing bars. Onlythose knockouts are removed, to provide holes for the reinforcing bars,as are needed for reinforcing bars. Thus, suflicient knockouts can beprovided to permit holes to be made for reinforcing bars for the mostdifficult situations but, where fewer reinforcing bars are required, noleakage occurs.

In order to aid in the setting up of the form members on the pouringfloor or curing slab 36, corners 56 (see particularly FIGS. and 6) areemployed. Each of the corners is identical, and comprises an uprightwith two flanges 58 secured at right angles to each other. Flanges 58are notched at 60 to permit the passage of reinforcing bars near thecorner should such be required in the particular precast tilt-upconcrete module being poured. Flanges 58 are secured to foot 62 whichpermits the corners to be secured to the casting floor 36. Holes 64 inthe foot permit suitable securement means such as removable anchorfasteners to be driven through the foot into the casting floor.

For layout of the form, four corners 56 are appropriately positionedupon curing slab 36 in accordance with the required dimension of thedesired precast tilt-up concrete module. The standard for such modulesis 19 feet wide by 21 feet tall, although the size may vary from 7 feetwide to 30 feet tall, for 6-inch thick modules, and other dimensions forthicker modules. After placement of the corners, left and right formmembers 38 and 40 are positioned within the corners to extend all theway into the corners, as is illustrated in FIGS. 4 and 5. This providesfor the points and channels of the side form members to extend all theway from top to bottom of the modules. Thereafter, top and bottom formmembers 42 and 44 are placed between the left and right form members atthe ends thereof, within corners 56. Thus, the top and bottom formmembers help hold the side form members out against the corners duringfurther assembly. Additional corner holes 64 in the flanges 58 permitsuitable securement means such as sheet metal screws to be driventhrough the flanges into the form members.

The proper knockouts 54 on the side form members had been knocked outprior to their being placed, as a preferable measure, although theknockouts can be removed after the side form members are positioned inthe corners. The next step is the placement of reinforcing bars 66. Asufficient number of these bars is placed in accordance with the overalldimensions of the particular precast tilt-up concrete module and theconcrete strength. Reinforcing bars from inch to l-inch diameter areemployed normally in accordance with requirements. Reinforcing bars 66are of sufficient length to extend out through the openings in the formmembers so that they can be cast into pilaster 26, as is illustrated inFIG. 3. In that figure, the reinforcing bars are indicated at 28 and 30respectively in modules 22 and 24. Another reason for permitting thereinforcing bars to extend out through the side form members is that,with the installation of appropriate reinforcing bar clamps, thereinforcing bars can be employed as waler rods during the pouring toprevent spreading of the side form members.

The preferred embodiment of the clamp of this invention is generallyindicated at 102 in FIG. 19. Clamp 102 has a baseplate 104 which hasopening 106 therein. Body 108 is in the form of an open-sided tube andis positioned over opening 106, and is secured to baseplate 104. Thus,an opening extends through opening 106 and body 108. Additionally, theside of both the baseplate and the body are open so that a reinforcingbar may be inserted into the side of the opening in the body.

Clamp bolts 110 and 112 are threadably engaged in body 108 and areangularly related to each other at approximately and are directed fromadjacent the open edges of the opening in the body and the baseplatetoward the closed, inner side thereof. Thus oriented, clamp bolts and112 are adapted to engage on reinforcing bars of any size which are ableto pass into the opening. The ends of the clamp bolts engage on the barand force the bar into the back side of the body, and clamp the barthereagainst. Thus, tight and rigid clamping is accomplished in theU-shaped body formed by the open-sided tube.

Additionally, clamp 102 has an angularly positioned flange foot 114thereon. Flange foot 114 is preferably integrally formed with baseplate104 so that they are part of the same rigid structure. Foot 114 has atleast one hole 116 therein which permits clamp 102 to be secured to theslab curing floor. Furthermore, clamp 102 has bolts 118 therein whichpermits the clamp to be secured against the adjacent form member by thedriving of nails and screws therethrough.

An additional clamp in accordance with this invention is illustrated inFIGS. 5, 10, 11, 13 and 14 and is generally indicated at 68. Clamp 68has a flat baseplate 70 which is preferably of sufiicient size to extendacross all of the points on the form member with which it is to beemployed. Opening 72 is provided in the side of the baseplate, andU-shaped body 74 is secured to baseplate 70 and is superimposed overopening 72. As is best illustrated in FIG. 14, a U-shaped body 74 ispreferably in the form of a tubular cylinder having one side thereof cutout. The side openings in body 74 and baseplate 70 are of sufficientsize as to accept the largest reinforcing bar 66 with which clamp 68 isto be employed. Opposing clamp bolts 76 and 78 are threadedly engaged inopenings in body 74 so that the clamp bolts are substantially axiallyaligned as is indicated in FIGS. 13 and 14. Either body 74 may bethreaded, or threaded members such as nuts can be secured to the body,in the manner illustrated in these figures.

In use, at least one of the clamp bolts is backed off, and clamp 68 isslipped sidewards over the reinforcing bar 66. Baseplate 70 is engagedagainst the form member, and the backed 01f bolt is clamped against thereinforcing bar. Preferably, the reinforcing bar is substantiallycentered vertically in opening 72, by appropriate adjustment of theclamp bolts. The clamp bolts may extend different lengths for differentdiameters of reinforcing bar, but the structure is so dimensioned thatit can clamp on any size of reinforcing bar which is employed bytightening the bolts to force the reinforcing bar 66 into the back ofopening 72 against body 74, as illustrated. Securement means such assheet metal screws or other fasteners may be driven into the formmembers through holes 79 in the baseplate 70 to prevent lateral orrotary movement of the clamp and reinforcing bar. These figures indicatethe employment of clamp 68 in association with the form members increation of a precast tilt-up concrete module. However, it is equallyclear that clamp 102 may be so employed, together with the advantage ofmore secure clamping and with the advantage of securability of the clamp102 to the castingslab.

When all of the reinforcing bar 66 and their clamps 68 are installed,the side frame members are ready for pouring because the clamps permitthe reinforcing bars to act as Waler rods to prevent the side formmembers from spreading. However, the top and bottom form members needreinforcement to prevent deflection from the load of the poured concreteas it is poured.

The preferred embodiment of the reinforcement strongback is generallyindicated at 120 in FIG. 20. Strongback 120 has a baseplate 122 which ispreferably substantially as wide as the points on the top and bottomform members so that the baseplate can engage upon all of the points.Furthermore, the baseplate is fairly long, and may be as long as the topand bottom form members. However, it is preferably somewhat shorter, forexample, one-third to one-half that length, for convenience in handlingto prevent the weight of a single strongback from becoming too great.

Strongback 120 has housings 124 and 126 thereon which are in the form ofangle irons having their flanges secured to the back of the baseplate.Housings 124 and 126 are positioned at the ends of the baseplate to actas a guide for tongue 128. Tongue 128 is in the form of an angle ironwhich is substantially equal to the length of baseplate 12 2. Thus, whenthe tongue is not extended, it is retained by housings 124 and 126.However, bolt 130, which is threaded through tongue 128, can be loosenedand employed as a handle to slide tongue 128 to the right, to the dottedline position. In that position, bolt 130 is tightened down, as is bolt132, to retain the tongue in the extended position. In the extendedposition, the tongue enters into the housing 124 of the adjacentstrongback (not shown) and is secured therein by tightening bolt 134.Thus, a series of strongbacks can be arranged so that they have aninterengaging configuration. Any reasonable length can thus be assembledout of a plurality of strongbacks 120 to accomplish the strengthening ofa top or bottom form member.

Holes 136 permit securement of the strongback to the form members by thedriving of nails or screws through these holes and through the formmember. This reinforcement on the top and bottom form members gives thenecessary strength to the form members in the longer length to resistexcessive deformation during pouring. Additionally, strongback 120 hasfoot 138. Foot 138 is a flanged foot, preferably formed integrally withbaseplate 122 so as to be rigid and secure with respect thereto. Foot138 has holes 140 therein and, by the employment of nails or othersuitable securing means through holes 140, the strongback can be securedto the curing floor. Thus, rigid strongback securement and positioningmaintains the strength of the top and bottom form members.

An additional strongback construction is illustrated in FIGS. 4, 5, 9,12 and 15. The strongback illustrated therein is capable of the sameemployment, except for the securement to the pouring floor because ithas no integral foot. It is clear, however, that the strongback of FIGS.9 and 12 can employ an integral foot, if such construction is desired.Furthermore, the housing construction of the strongback 120 need not beemployed in conjunction with an integral foot, but can be employed on asimple baseplate such as that described with respect to strongback 30.

Reinforcement strongbacks for the top and bottom form members areillustrated in FIGS. 4, 5, 9, 12 and 15. The strongbacks are generallyindicated at 80. Strongbacks have baseplate 82 which is preferably ofsufficient dimension to engage all of the points on the upper and lowerform members. To the outside of the baseplate 82 is secured housing 84,which may be in the form of an angle iron as illustrated. Positionedinteriorly of one end of housing 84 and extending therefrom is tongue86. Tongue 86 is permanently secured within the housing, and is of suchlength as to extend therefrom on one end and leave the other end ofhousing 84 vacant for the reception of an adjacent tongue. Lock bolt 88is threadably engaged in housing 84 adjacent the vacant end of thehousing.

Thus, when adjacent strongbacks 80 are put in place, the tongue on onestrongback engages in the vacant end of the housing on the other so thatthe two strongbacks are rigidly secured together. Securement is enhancedby tightening of lock bolt 88. In use, an appropriate number ofstrongbacks 80 are assembled longitudinally of each other and arepositioned against the top and bottom form members, as is illustrated inFIGS. 5, 12 and 15. Tongue 86 on the end strongback engages aroundcorner 56 to help hold the top and bottom form members outward prior tothe pouring of concrete. The strongbacks are secured to the form membersas by double-headed nails 90 or preferably sheet metal screws whichengage through appropriate holes 92 in baseplate 82 and through the topand bottom form members, as is illustrated in FIG. 15.

The top and bottom form members have been illustrated in FIGS. 4, 5, l2,l5 and 18 as lying at right angles with respect to the pouring floor. Itwill be appreciated that in some cases it is desirable that the top ofthe precast module have an outward slope for the engagement of a roofthereon at the appropriate angle, or roof beams at roof pitch, or forother reasons. In any event, in some cases it is desirable for one orboth of the top or bottom form members to lie at an angle other thanperpendicular with respect to the pouring floor.

Support bracket 142 is generally indicated in FIGS. 21 and 22 as beingemployed in association with strongback 80. It is clear, however, fromthe manner of employment of support bracket 142 that its utility residesin the angular support of the strongback and this is independent ofwhether or not the strongback tongue is fixed or movable. Accordingly,either strongback 80 or strongback could be employed therewith,providing the foot 138 of strongback 120 was arranged to be positionedout of the way. Alternatively, a strongback as indicated at 120- couldbe employed without the foot 138, and accordingly would be freelyinterchangeably usable with support bracket 142.

Support bracket 142 comprises baseplate 144 to which is secured foot146. Foot 146 is arranged to be supported on and secured to the pouringfloor so as to secure the support bracket 142 in any desired location.Jack-screws 148 and 150 are threaded in baseplate 144 so that theirmanner of extension can be selected. A pair of nuts 152 is lockedtogether on the outer end of the jack-screws to serve as a handle meansfor turning the jack-screws to position them at an appropriate positionof extension through the baseplate. The outer end of each jack-screwcarries a portion of a sphere, as is indicated in detail in FIG. 23.Here the portion of the sphere 154, or shape similar thereto, engages inan appropriate mating hole 156 in channel 158.

As is indicated in dotted lines in FIG. 23, the substantially sphericalshape of ball 154 in the appropriate hole 156 permits channel 158 to lieat an angle with respect to the axis of jack-screws 148. A similarchannel 160 is mounted upon a similar ball-like shape on the end ofjack-screw 150. Nuts 162 and 164 are respectively mounted in pairs onjack-screws 148 and 150 behind the channels. Thus, when the appropriatepositioning is obtained, nuts 162 and 164 may be tightened up againstthe back of the channel, while nuts 152 can be tightened up against theback of the support bracket. This maintains the appropriate angularrelationship. By this means, both the top and bottom form members can bearranged at the desired angle for the particular module being precastfor tilt-up. Furthermore, if the strongback remains in position from onecasting to the next, each of the top and bottom angles remains the same,to permit and provide for consistent results. A plurality of restrainingwires 166 may be anchored to reinforcing bars 66 as by twisting an endthereabout, with the other end similarly secured to the inturned upperflange 50 at respective holes 52.

The precast tilt-up concrete module is provided with an appropriatenumber of suitably located conventional lifting points so that, uponcompletion of pouring and curing, the finished module can be lifted intoplace. The forms are now ready for pouring.

After concrete pouring and curing, certain portions are removed beforelifting. Clamps 68 are removed by loosening one of the bolts, andstrongbacks 80 are removed by pulling the nails 90. Now the precasttilt-up concrete module is ready for lifting into place. Prior tolifting, during lifting or after lifting, any leakage or flash from theconcrete is easily knocked 01f. There may be some concrete leakagethrough reinforcing bar holes 54, but normally, this is not ofsufiicient volume to warrant correction. Additionally, there will besome leakage at each corner between the juncture of the side forms andtop and bottom forms. However, this leakage is normally suflicientlycontrolled by the corners 56 that hand work is unnecessary.

After placement of the tilt-up module with its form members 38, 40, 42and 44 in place, a suitable pilaster 26 is poured. The extension of thereinforcing bars into the pilaster provides rigid joining. Furthermore,the employment of the forms at the interface between the pilaster andthe modules prevents seepage of water through the crack therebetween.Since the form metal is not hygroscopic, any water that reaches theexterior portion of this crack runs to the bottom rather than seepsinwardly into the building. Furthermore, the top form member 42conveniently aids in finishing off the roof structure because nails morereadily attach through the metal form to permit more secure fastening ofturret and roof elements.

Referring to FIG. 18, the use of corners 56, clamps 68 and strongbacks80 is illustrated in connection with a conventional wooden form. In thiscase, these articles are employed in the same manner, but are secured tothe removable wooden form instead of being employed in conjunction withthe permanent form. Thus, corners 56 are secured to the pouring andcuring slab and the wooden forms are assembled therein. The corners aidin restraining the wooden form in position during assembly and pouring.Clamps 68 or 102 are positioned on the appropriate wooden side formmembers and strongbacks or 120 on the top and bottom wooden formmembers. Upon disassembly, corners 56 need to be removed so that thewooden form members can be removed from the precast slab before tilt-up.

Referring to FIG. 17, module 22 is illustrated as lying against a module94. As is clear from FIG. 3, when a pilaster is poured between modulesof the preferred embodiment of the tilt-up concrete module, identicalform members are used. However, when smooth surfaces are desired on theinside and outside of the jointed modules, an alternative form 96 isemployed. Such a form is employed where modules lie directly adjacent toeach other, as in walls for flood control channels and the like. In sucha case, mastic 98 or a comparable material is employed between the formmembers upon assembly. Form 96 provides points and channels facingoutwardly as to mate with the form member 40. Inturned flanges 100 arepositioned parallel to flanges 48 and are directed inwardly in such aposition as to engage in and lock in the concrete of the module. Holesare provided in the inturned flanges to permit concrete bondingtherethrough.

The invention having been described in its preferred embodiment, andalternative or modified embodiments disclosed, it is clear that thisinvention is susceptible to numerous modifications and embodimentswithin the ability of those skilled in the art and without the exerciseof the inventive faculty.

What is claimed is:

1. The process of producing a building from precast tilt-up concretemodules having a permanent form thereon, comprising the steps ofpositioning a plurality of permanent form members on a pouring floor insubstantially abutting relationship, with the permanent form membersbeing attached to the pouring floor only for purposes of maintainingalignment, the permanent form members being related to each other insuch a manner as to form a sutficiently rigid form without applyingtensile stresses in the pouring floor;

positioning reinforcing bars across the area defined by the form membersand through opposite form members; clamping at least some of thereinforcing bars with respect to the opposite form members so thathorizontal stresses on the form members as a result of pouring concretetherebetween are equalized between each other and opposed by thereinforcing bars;

pouring concrete in the area defined by the form members to produce aconcrete module having a permanent form thereon; and

tilting the module up to form a part of a wall.

2. The process for producing a building from precast tilt-up concretemodules comprising the steps of:

disposing a plurality of permanent form members on a pouring floor in anenclosing formlike relationship; inter-engaging the form members so thatthe stresses of pouring concrete therebetween are transferred betweenthe form members without substantial tensile stress on the pouringfloor, said inter-engaging step including positioning reinforcing barsthrough opposite form members; and clamping at least some of thereinforcing bars with respect to the opposite form members so that thespreading loads on opposite form members are transferred as tension tothe reinforcing bars; pouring concrete into the enclosure defined bysaid permanent form members to produce a concrete module having apermanent form thereon; and tilting up the module with the form membersthereon so that the module is positioned to serve as a building wall.

3. The process of claim 2 further including:

tilting up a plurality of precast concrete modules with the edgesthereof spaced from each other; and

r 11 pouring a concrete pilaster in engagement with the edges of thetilted-up concrete modules.

4. The process for producing a precast tilt-up concrete module having apermanent form thereon, comprising the steps of:

forming a plurality of permanent form members with an inturned flange;

securing corners on the pouring floor;

positioning a plurality of such permanent form mem- "bers on a pouringfloor in substantially abutting relationship and into the corners torestrain the permanent forms;

pouring concrete into the area defined by the form members so that theconcrete permanently interlocks with the form members including byflowing behind the inturned flanges so that the form members permanentlyremain on the module and define the edges thereof; and tilting up themodule with the form members thereon. 5. The process of producing abuilding from precast tilt-up concrete modules having a permanent formthereon, comprising the steps of:

securing corners onto a pouring floor; positioning a plurality ofpermanent form members onto the pouring floor in substantially abuttingrelationship and into the corners to maintain the permanent form membersin alignment prior to and during pouring of concrete therein with thepermanent form members being attached to the pouring floor only forpurposes of maintaining alignment, the permanent form members beingrelated to each other in such a manner as to form a sufliciently rigidform without applying tensile stresses in the pouring floor;

pouring concrete in the area defined by the form members to produce aconcrete module having a permanent form thereon; and

tilting the module up to form a part of a wall.

6. The process for producing a building from precast tilt-up concretemodules comprising the steps of disposing a plurality of permanent formmembers on a pouring floor in an enclosing formlike relationship;

positioning reinforcing bars through opposite form members;

clamping at least some of the reinforcing bars with respect to theopposite form members so that the spreading load on opposite formmembers of pouring concrete therebetween are transferred as tension tothe reinforcing bars without substantial tensile stress on the pouringfloor;

pouring concrete into the enclosure defined by said permanent formmembers to produce a concrete module having a permanent form thereon;

unclamping the reinforcing bars; and

tilting up the module With the form members thereon so that the moduleis positioned to serve as a building Wall.

7. The process of claim 6 further including:

tilting up a plurality of precast concrete modules with the edgesthereof spaced from each other; and

pouring a concrete pilaster in engagement with the edges of thetilted-up concrete modules.

References Cited UNITED STATES PATENTS FOREIGN PATENTS 1,238,437 7/1960France 52745 PRICE C. PAW, 13., Primary Examiner US. Cl. X.R.

